This invention relates to a starting and operating apparatus for a fluorescent lamp and, more particularly, to a transistorized inverter apparatus for starting and operating a compact fluorescent lamp.
Transistorized inverter circuits for operating fluorescent lamps from a DC power supply are well known, a typical circuit being disclosed in U.S. Pat. No. 3,593,060, dated July 13, 1971. Such circuits normally operate the lamps at a relatively high frequency above the audible range which enhances the efficiency of operation. In addition, such circuits can be made relatively light as compared to the more usual inductive reactor ballast.
U.S. Pat. No. 3,579,026 dated May 13, 1971 to Paget discloses a transistorized inverter ballast in which a capacitor and transformer provide a tank circuit for the oscillations of the inverter.
In U.S. Pat. No. 3,371,244 dated Feb. 27, 1968 is disclosed a transistorized inverter circuit for operating a discharge device in which a parallelling capacitor is connected across the output winding of the inverter with an additional capacitor in series with the lamp. The parallelling capacitor is started to serve the purpose of reducing spike voltages reflected across the transistors and the series capacitor is described as included in order to improve the power factor of the circuit.